The present invention relates to a capsule for the preparation of a nutritional liquid or food compositions in a beverage preparation device.
Nutritional compositions can be, for instance, infant formulas or also nutritional liquids for toddlers, invalids, elderly people, persons having nutritional deficiencies or athletes. Food compositions can be dairy-based liquids, soup, coffee or tea beverages. These compositions are prepared from ingredients contained in a capsule by addition of a liquid such as hot or ambient water. The liquid may contain contaminants such as micro-organisms or solid particles. These contaminants should be removed from the liquid before the liquid is mixed with the ingredients.
In particular, infant formulas have been developed as a substitute for human breast milk in order to provide required nutrients to infants. In general the infant formulas are either based on cow or soy milk and may be provided in different forms such as powder or concentrated liquid.
Each of the different forms in which infant formulas may be provided has their own advantages. For instance, although the infant formula provided in a powder has a relative high nutritional quality, the preparation thereof is time consuming, since the water used for reconstitution must be boiled in advanced and allowed to cool then poured into a sterilised drinking vessel containing the powder in order to prepare a ready-to-feed liquid infant formula.
If prepared and consumed in this manner, powdered infant formulas provide a safe and nutritionally good substitute for mother's milk in the situations described above. However, the process needs to be repeated every time a feed is required. It may readily be seen that this may not always be convenient and, as a consequence, many parents and other caregivers do not prepare the formulas properly and hence expose the infant to the risk of infection. Alternatively, batches of the infant formula may be prepared and then stored until needed. Unfortunately, if any pathogen has contaminated the formula, it may have time to replicate in certain storage conditions.
In further development, infant formulas in ready-to-feed single serve portions have been introduced which overcome the inconvenience of the preparation of the infant formula. However, these ready-to-feed products are more costly than infant formulas stored in bulk and there is the same need to consume the formula immediately after opening to avoid the risk of contamination with bacteria.
The immune defences of infants and young children are generally not fully developed and, as a result, these populations are particularly vulnerable to both bacterial and viral infections. For example, they may be prone to infections in circumstances where the immune system of a healthy adult would resist infection or they may suffer more serious consequences as a result of infection than would a healthy adult. Similar difficulties may arise in populations where the immune system is compromised such as the elderly. The consequence of this is that devices that prepare nutritional compositions which are perfectly safe for healthy adults may not be able to produce products which meet the increased safety standards required for products to be consumed by subjects having immature or compromised immune systems.
More generally, the liquid (e.g. water) used for the preparation of the nutritional liquid or food can contain particles which may be allergens or may be undesired for many other different reasons.
Therefore, there is a need for a method or an apparatus which enables provision of nutritional composition for instance an infant formula or other food compositions in a convenient and safe manner.
WO2006/077259 discloses a method for preparing a single serving of a nutritional composition comprising introducing liquid such as water into a cartridge containing a unit dose of the composition in concentrated form. Thereby, the water is treated prior to the introduction into the cartridge in order to remove pathogens from the water. This treatment may be for instance a pre-heating, a filtering or an irradiation of the water with ultra-violet light.
A device which teaches the principle of treating water by means of a filter used for the preparation of nutritional compositions in a dispenser from capsules is disclosed in co-pending European patent application No. 06117801.8 filed 25 Jul. 2006 entitled “Dispenser for preparing a nutritional composition”.
A capsule with an integrated antimicrobial filter has been described in co-pending European patent application No. 08100900.3 filed 24 Jan. 2008.
In particular, it desirable to ensure that the filter is strategically placed in the capsule to avoid any risk of clogging by the nutritional/food solids contained in the capsule and also to ensure a complete delivery of the nutritional product from the capsule. It is also desirable to ensure a full dissolution/dispersion and proper mixing of the ingredients with the liquid fed in the capsule to ensure the full nutritional delivery from the capsule. A proper interaction can be obtained if there is also sufficient velocity of the liquid entering the ingredient's compartment. When the filter is placed upstream of the compartment, the risk of clogging with components such as fat and/or proteins is avoided but the liquid velocity is significantly reduced after it has passed the filter when it interacts with the ingredients. The dissolution/dispersion of the ingredients and mixing in the liquid can therefore be insufficient. As a result, there is a risk that the capsule is not correctly emptied but a significant amount of solids residue is left in the capsule, thereby not ensuring the desired nutritional content in the delivered mixture.
The present invention aims at solving the aforementioned problem as well as others which will be developed in the present specification.